High quality epidemiologic and comparative effectiveness research is needed to inform the health system about how to best care for people with multiple chronic illnesses since approximately one quarter of Americans fit this designation. The intent of the proposed work is to greatly enhance the capability of an existing, successful primary care practice-based research network (PBRN) to conduct these kinds of research. The work will be done in Practice Partner Research Network (PPRNet), a national PBRN among 156 primary care practices in 40 States who use a common electronic medical record (EMR) and pool nonidentifiable data for quality improvement and research. PPRNet researchers, located at the Medical University of South Carolina, will conduct the work, which will comprise of both infrastructure development and conduct of a primary research project designed to test the capability of the new infrastructure. Infrastructure development planned includes a set of activities intended to expand PPRNet to at least 250 practices and development of sophisticated computer algorithms to enhance the ability of researchers to identify patients with any of 20 chronic medical conditions. The primary research project will be a cross-sectional epidemiologic study, comparing the delivery of recommended preventive services among patients with no chronic illness, one chronic illness, and multiple chronic illnesses. To date there is inadequate information about the relationship between chronic illness and receipt of preventive services. The proposed research will address this issue and findings will likely lead to a variety of investigations designed to improve preventive services delivery to patients with multiple chronic illnesses. PUBLIC HEALTH RELEVANCE: Understanding the intent to which patients with multiple chronic illnesses receive recommended preventive services and designing strategies to improve this aspect of medical care are important priorities for the U.S. health care system. The activities planned in this proposal will further develop capabilities of an existing primary care practice based research network to conduct this research and support its research designed to address these issues.